TABLE 4.
Posterior densities of Bayesian latent class main model with informative priors on thoracic ultrasound (TUS) and Wisconsin calf respiratory score (WCRS) for the diagnosis of bronchopneumonia (BP) in 330 dairy calves using 3 different auscultation (AUSC) definitions.
| Informative priors for TUS and WCRS | ||||||||
|---|---|---|---|---|---|---|---|---|
| Auscultation 1 (0 vs 1+) | Auscultation 2 (0, 1 vs 2+) | Auscultation 3 (0, 1, 2 vs 3+) | ||||||
| No covariance | Covariance | No covariance | Covariance | No covariance | Covariance | |||
| Test | Parameters | Priors | Median (95% BCI) | Median (95% BCI) | Median (95% BCI) | Median (95% BCI) | Median (95% BCI) | Median (95% BCI) |
| AUSC | Se | beta (1,1) | 0.903 (0.812‐0.984) | 0.895 (0.808‐0.973) | 0.817 (0.691‐0.945) | 0.801 (0.684‐0.912) | 0.679 (0.557‐0.828) | 0.661 (0.548‐0.788) |
| Sp | beta (1,1) | 0.574 (0.466‐0.715) | 0.547 (0.454‐0.719) | 0.908 (0.811‐0.990) | 0.872 (0.787‐0.981) | 0.985 (0.938‐0.999) | 0.976 (0.932‐0.998) | |
| TUS | Se | beta (4.62,0.86) | 0.816 (0.666‐0.981) | 0.870 (0.670‐0.992) | 0.790 (0.686‐0.905) | 0.836 (0.706‐0.939) | 0.878 (0.798‐0.951) | 0.894 (0.814‐0.958) |
| Sp | beta (77.55,4.4) | 0.908 (0.834‐0.0.968) | 0.915 (0.844‐0.972) | 0.882 (0.810‐0.990) | 0.892 (0.823‐0.958) | 0.897 (0.821‐0.963) | 0.910 (0.840‐0.969) | |
| WCRS | Se | beta (21.47, 13.29) | 0.570 (0.482‐0.662) | 0.578 (0.479‐0.675) | 0.594 (0.505‐0.687) | 0.608 (0.514‐0.698) | 0.595 (0.507‐0.685) | 0.597 (0.509‐0.686) |
| Sp | beta (53.79,19.11) | 0.794 (0.727‐0.856) | 0.786 (0.720‐0.851) | 0.806 (0.747‐0.858) | 0.804 (0.745‐0.856) | 0.786 (0.730‐0.837) | 0.789 (0.733‐0.840) | |
| BP prevalence | P(BP) | beta (1,1) | 0.469 (0.349‐0.607) | 0.447 (0.342‐0.608) | 0.459 (0.352‐0.570) | 0.443 (0.348‐0.552) | 0.420 (0.329‐0.508) | 0.425 (0.342‐0.508) |
| Covariance | covDn | a | – | −0.006 (−0.024‐0.022) | – | −0.009 (−0.025‐0.017) | – | −0.007 (−0.024‐0.018) |
| covDp | b | – | −0.054 (−0.008‐0.048) | – | −0.017 (−0.054‐0.033) | – | −0.021 (−0.049‐0.010) | |
| DIC | DIC | 46.7 (39.1‐56.8) | 47.6 (39.7‐58.1) | 47.0 (38.9‐59.1) | 47.5 (39.3‐60.3) | 46.0 (38.3‐56.9) | 44.8 (37.3‐56.1) | |
Note: AUSC1 (score of 0 [negative] vs ≥ 1 [positive]), AUSC2 (score of 0 or 1 [negative] vs ≥ 2 [positive]), and AUSC3 (score ≤ 2 [negative] vs ≥ 3 [positive]) were associated with different definitions based on auscultation findings (see Table 1). Calves with a WCRS ≥5 were considered positive. Calves with a maximal consolidation depth ≥3 cm with TUS were considered positive.
Abbreviations: covDn, covariance between TUS and WCRS in truly negative animals; covDp, covariance between TUS and WCRS in truly positive animals; DIC, deviance information criterion; Se, sensitivity; Sp, specificity.
min (Se‐WCRS, Se‐TUS) − Se‐WCRS × Se‐TUS.
min (Sp‐WCRS, Sp‐TUS) − Sp‐WCRS × Sp‐TUS.